Fluid-heater control



Patented Aug. 18, 1925.

UNITED g*stares assaut VPATazur oFFieE.

ALFRED HoEMaNN, on DUISBURG, GERMANY, AssTeNoR To THE RABo'ocK ak wILcoX COMPANY, or BAYONNE, NEW JERSEY. ,a CORPORATION or NEW JERSEY.

FLUID-HEATER CONTROL.

Application filed september 1e,y 1922. serial No. sa'z;

To @ZZ LU/1,0m t may concern:

Be it known that I, ALFRED HOEMANN, a citizen ot Czechoslovakia, residing at Duisburgn Germany, have invented certain new 5 and usetul Improvements in Fluid-IIeater Controls, of which the following is a speciilication.

The object of my invention is the provision of simple and effective means Jfor controlling the temperature of a fluid heater.

My present invention will best be understood from the following description and the annexed drawing in which Figure 1 is a vertical, longitudinal section of a steam boiler economizer with its: setting which I have chosen for the purpose of illustrating my invention, andFig. 2 is a sectional view through the thermometer and the associated parts. n Y

In the drawing, a Hue has connected to it an inlet Hue 11 and a-n outlet fine 12. Connecting` the inlet flue 11 and the outlet flue 12 is a lay-pass flue 13. In the flue 10 s, is an economizer of a well known type, having a pluralityI of sections 14, 27 and 28 ot vertical tubes connected at the top and bottom by headers, the Sections: being connected to each other by pipes 29 and 30, the inlet ot the economizer 15 providing an entrance for the cold water at the bottom of the first section and the outlet 16 providing an e-Xit Vlor the heated water at the top ot' the last section, The gases flow through the flues in the direction indicated by the arrows, and it will be seen that the general course of the water is counter to that ot the flow of the gases: that is, the water enters at 15 and flows: up through the tubes of the section 14, thence down through pipe 29 to the bottom of section 27 and again downl through pipe 8O to the bottom of section 28, leaving at the outlet 16.

In this form oit economizer, any steam' formed in the last and hottest section 28 will pass up to` the top headers and will pass ott readily through the outlet 16 without seriously interfering with the operation of the economizer. It steaming occurs in any section except the last, however, such steam would have to be carried downward through pipes 29 and 30 and this might interfere seriously with the operation. Hence, I have provided an arrangement by which the pg Of the hot gases over the economizer may be controlled automatical-y ly, preferably in accordance with the k,temsperature of the water in the neXt to the last or hottest section.

Dampers 17 are provided at the entrance ot the by-pass flue. 13, these dempers: heilig shown as double in form and interconnected, and operated in a manner to be described more Jfully hereinafter.

A thermon'ieter 1S is provided ata point son'rewhere near the outlet 16 of the econoniizer, and preferably at the top of the next to the hottest section, they thermometer being arranged so that it is affected by the tem- Y perature ot the water flowing through the economizer. The thermometer shown is ot the expansible-tluid type, andthe mercury usually used in such a thermometer is"l caused to move a contact member, so that, at a predetermined teniperature, a circuit is closed through the wires 19 and 2O and a motor 21, which is connected by gearing 22 with ,one otl the dampers 17, this latter damper being, in turn, connected through a link` 23 with the other hall ot the damper.4 t

It desired, additional dam'pers 24 and 25 may be provided at. the entrance and exit, respectively, ot the flue 10.r Also, if desired, a signaling device such as a lamp 2G, may be provided to be operated at the time that the circuit through 19 and 20'is closed.

In practice, the dampers 17 will be closed normally, so that all of the hot gases vtrom the flue 11 will pass across the economizer tubes and out of the outlet 12,.` If, however, because of changes in the boiler operating conditions, the temperature of the gases rises unduly, or it, for any reason, the How of water through the economizer is cut down, it will then become desirable to prevent an undue rise ot pressure in the econo' mizer, and my invention will accomplish this. By locating the thermometer 18 at a point somewhere near the outlet, it will be evident that if, because of operating condi-A tions, the temperature of the water rises to a predetermined point, the electric circuitsr through the motor 21 will be closed and the dampers 17 opened, to shunt or bypass some of the gases around the economizer.

By locating the thermometer in the next to the hottest section, the temperature at which the dampers operate to shunt the gases may be suchas to insure that no steaming will take place Yin any section eX,-

cept the last, and yet maintain the water leaving the economizer at a temperature which may cause steaming.

By the use of a signaling device, such as the lamp 2G, the attention 'of the operator may be called to the operating conditions when the automatic device operates. If desired, the automatic feature may be dispensed with, and the operator will then move the appropriate dampers by hand when the signal indicates the changed operating conditions.

Instead of moving the damper l? to full open or closed position at each operation, provision may be made to cause the damper to be only partially opened or closed at each operation, so that'each successive rise or fall of the temperature will cause a partial opening or closing of the damper; that is to say, the damper will be moved by successive steps.

I claim 1. In combination, a flue for hot gases, a fluid heater in the flue, said heater having an inlet andan outlet whereby fluid may flow therethrough while being heated, a thermometer in the fluid near the cutlet, an electric circuit including a signal, and arranged to be closed when the temperature indicated by the thermometer reaches a predetermined point.

2. In combination, a flue for hot gases, a fluid heater divided into-sections and located in said flue, inlet and outlet connections to the fluid heater and between the sections thereof to cause the water to flow succes sively through the sections in a general direction opposite to that of the hot gases through the flue, a by-pass for the hot gases around the fluid heater, and automatic means, controlled by the temperature of the fluid being heated in the next to the hottest section of the economizer, to regulate the flow of the gases through the by-pass.

3. In combination, a flue for hot gases, a

fluid heater divided into sections and located in said flue, inlet and outlet connections to the fluid heater and between the sections thereof to cause the water to flow successively through the sections in a general direction opposite to that of the hot gases through the flue, a by-pass for the hot gases around the fluid heater', a thermometer in the fluid near the outlet of the next to the last section of the fluid heater, and automatic means, controlled by said thermometer, to regulate the flow of the gases through the by-pass.

Ll. In combination, a horizontal flue for hot gases, a fluid heater therein, having a plurality of' sections comprising vertical tubes connected by headers, inlet and outlet connections to the fluid heater and between the upper and lower headers of adjacent sections arranged to cause the water to flow successively through the sections in a general direction opposite to that of the hot gases through the flue, a by-pass for the hot gases around the fluid heater, and automatic means, controlled by the temperature of the fluid being heated in the next to the hottest section ofl the economizer, to regulate the flow of the gases through the by-pass.

5. In combination, a horizontal flue for hot gases, a fluid heater therein, having a plurality of sections comprising vertical tubes connected by headers, inlet and outlet connections to the fluid heater and between the upper and lower headers of adjacent sections arranged to cause the water to flow successively through the sections in a general direction opposite to that of the hot gases through the flue, a by-pass for the hot gases around the fluid heater, a thermometer in the fluid near the outlet of' the next to the last section of the fluid heater,fand automatic means, controlled by said thermometer, to regulate the flow of the gases through the by-pass.

ALFRED HOFMANN. 

